Fatty Liver (cont.)

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

Fatty liver and diet

Nonalcoholic fatty liver disease has been associated in human or animal studies with reduced amounts of unsaturated fats (a diet high in saturated fat) and increased amounts of fructose (which is most commonly added to the diet as high-fructose corn syrup). Benefits of increasing unsaturated fat (a diet lower in saturated fat, and higher unsaturated fat) and reducing high fructose corn syrup on
nonalcoholic fatty liver disease have not been demonstrated; however, there is little harm in doing so, especially since there may be benefits of these dietary modifications unrelated to the liver.

An interesting observation - though unexplained - is that there is less scarring (fibrosis) in the livers of patients with NASH who drink more than two cups of coffee per day. (Scarring or fibrosis is the process that ultimately leads to cirrhosis.) Similar benefits of coffee have been associated with lesser degrees of liver disease in both alcoholic cirrhosis and hepatitis C. It is not unreasonable to recommend drinking coffee in moderate amounts in view of the lack of harmful side effects.

Vitamin D deficiency is associated with
nonalcoholic fatty liver disease. Although there is no reason to think that this deficiency contributes to
nonalcoholic fatty liver disease, it is reasonable to measure vitamin D levels in patients with
nonalcoholic fatty liver disease and treat them with vitamin D if they are deficient.

There is no evidence of harmful effects of light alcohol consumption (two or fewer drinks per day
for men, one or fewer for women) on
nonalcoholic fatty liver disease though there also is no evidence that it is safe! Larger amounts of alcohol consumption should be avoided by everyone, including individuals with
nonalcoholic fatty liver disease.

Fatty liver, weight loss, and exercise

Since the serious complications of nonalcoholic fatty liver disease are primarily seen in patients with NASH, treatment of NASH is of great importance. Unfortunately there are no clearly effective treatments for these patients. One of the difficulties in identifying effective treatments is the need for long-term studies since the progression of NASH to cirrhosis and its complications occurs slowly. Several treatments have resulted in a reduction of fat in the liver, but few have shown that the progression of NASH is slowed.

Weight loss and exercise are among the most promising of treatments for
nonalcoholic fatty liver disease. It does not take large amounts of weight loss to result in a decrease in liver fat. A
less than 10% decrease in weight may be enough. Vigorous exercise results in a reduction of liver fat and also may reduce the inflammation of NASH. The long-term effects of weight loss and exercise on the important development of cirrhosis and its complications are unknown. Nevertheless, at the present time, the best theoretical approach to
nonalcoholic fatty liver disease is weight loss and vigorous exercise. Unfortunately, only a minority of patients are able to accomplish these.